1. Field of Invention
This invention relates to garage door openers, specifically to a technique for providing a method for accurately positioning a vehicle a fixed distance from the front wall of a garage.
2. Description of Prior Art
Ever since the turn of the century when Henry Ford made automobiles a household item, the owners have been struggling with parking larger and larger vehicles in garages which often are barely large enough to hold the vehicle let alone the bicycles, lawn mowers, etc. which all need to be stored in the garage. In an effort to provide a guide to avoid running into the extra equipment and also provide a path to get around the front or the back of the vehicle, a number of techniques have been used. Placing a piece of lumber, such as a 2.times.4, on the floor or hanging a tennis ball from the ceiling provides a very simple and inexpensive solution, but both have significant disadvantages. In the case of the 2.times.4, the driver is never certain as to whether the 2.times.4 has been inadvertently kicked from its' desired location while the vehicle was out of the garage. Gluing or bolting the 2.times.4 to the floor can solve the problem of accidental displacement, it now becomes dangerous to the point where some one accidentally contacting the 2.times.4 may trip and injure himself. Also, permanently attaching the 2.times.4 to the floor requires that it be removed and relocated when the next vehicle is purchased. Although the tennis ball will not move because it is permanently attached to the ceiling and does not create a safety hazard, it does become very annoying to continually walk around the dangling tennis ball or balls in the case of a two car garage if the garage is used for anything other than parking a vehicle.
A product, which is slightly more sophisticated than the 2.times.4, is sold on the market for 29.99 a pair. It is sold as the "Park Smart Mat". This product consists of a mat with two rubberized bumps spaced about a foot apart, and is made of super durable, highly visible yellow rubber-like material, which is oil and gas resistant. The mat is placed on the garage floor so that the front wheel will be located between the two bumps when the vehicle is positioned the desired distance from the front wall. This product obviously suffers from the same problems as the 2.times.4. It can be kicked out of place and tripped over.
A number of more costly solutions are also on the market. One device called the "StopLite Vehicle Positioning System" consists of two parts. One piece is mounted on the ceiling above the vehicle. A second unit is mounted on the wall in front of the vehicle. The ceiling unit contains an infrared sensor that monitors the position of the vehicle. The second unit, which is mounted on the front wall, flashes yellow as the vehicle enters the garage and then red when the vehicle reaches the desired stopping point. This product requires the annual replacement of two batteries, one in the wall unit and one in the ceiling unit. Adjusting the overhead sensor requires climbing up on a ladder and adjusting the mounting plate of the sensor. Another shortcoming is that there is no continuous feedback of where the vehicle is relative to the desired stopping point. The unit flashes yellow telling you to slow down, but then abruptly turns red when you have reached the desired stopping point.
Another product on the market, called the Park-Zone, consists of two pieces connected by a coiled cord assembly similar the cord on a telephone handset. Both units are mounted on the front wall. The sensor unit is mounted at bumper level and contains an ultrasonic sensor by POLAROID.RTM.. The display unit is mounted above the sensor at roughly the eye level of the driver. This product has three lights (green, amber and red). The green light turns on as the vehicle enters the garage. Midway the green light turns off and the yellow lamp comes on. When the light changes to red you stop the vehicle. This product also suffers from the lack of continuous feedback of the vehicle's position relative to the desired stopping point. The green light illuminates as you enter the garage. Midway the amber light becomes illuminated and when you have reached the desired stopping point the red light illuminates. Thus, there is an abrupt change from amber to red. The operating instructions warn that the actual stopping point will vary depending on the reaction time of the driver and the speed at which the vehicle is moving when the light turns red. The instruction state to allow for a 6 to 12-inch variation in this stopping distance. This particular unit also continuously produces an audible "pinging" sound produced by the ultrasonic sensor. This can be very annoying if the garage is occupied for extended periods of time. The installation instructions also warn that activity in front of the car, such as during repairs, will keep triggering the display causing shortened battery life. The instructions also state that the sensor requires a flat surface to bounce the sound waves off of. This can be a problem on some vehicles that may have a relatively pointed bumper and no front license plate. Still another problem with this system is that, if the unit is powered from the AC power line, the device has to be re-calibrated after every power outage. Yet another problem is that the front wall can not be used for storage, since the sensor requires an unobstructed view of the front of the vehicle.